First of all, I know very little about 40 series. I'm a wagon guy :D

We had a visitor at our club meeting last week. He was driving a sweet 75 mustard 40 from airzona. We all went out to check it out and found a couple of interesting things. I want to give this guy some advise, but i need the right answers.

His front shackles were as far forward as they could be, completely level with the frame. It seemed like his leafs were too long. They were obiously not stock. The springs were about 48" long (it was dark out, so that may not be an accuracte measurement).

Out back his shackles were completely vertical. I measured those leafs as well, and came up with about 44"(again it was dark out).

We all looked at him and asked how it handled on the street. He had no problem, but the thing must have ridden like a brick on wheels. Good god! Bushings were shot too.

If I make an assumption that is leafs are backwards, ie put the fronts in the rear, am I correct? I'd like to help this guy out.

TIA.

:laughing:

Uh...yeah!

Ok that may have been a dumb question. I just hate to give someone bad advice.

Are the springs on a 40 different lenghts front and rear? Does that 4" differance in lenght seem right?

no, they are offset- longer toward the shackle i believe - don't know the exact measurement though, anyone?

let me rephrase that question. Is the overall length of the springs different on a 40 front and rear.

Nope, the springs are the same, same offset pin as well. Not sure what chef was suggesting. Old springs get flat, makes em ride better than rearched or lift springs. Was he complaining, or pardon me, are you just trying to point out something that is wrong.

He had no idea that there was a problem, but it was real obious to the rest of us. I cannot imagine that it was very fun to drive on the road. Sometimes ignorance is bliss. I called him up and asked him to re-measure the spring packs, just to make sure I'm not wrong.
These were aftermarket springs. I have no idea of the manufacturer.

Another thing, front shackles appeared to be stock length, and the rears had extended. Don't know if that relates to anything, but thought I'd add. We also measured the width of the springs and they were 2.5" wide.

Can anyone give me an example of the length of a stock 40 spring, and an aftermarket one?

FJ40 packs are 43.5" in length, 20" to the pin on the short side, 23.5" to the pin on the long side. Short side should connect with the solid frame mount in standard 90" wheelbase configuration.

Unfortunately, reversed packs have zero to do with shackles....just means wheelbase changes.

Verticle shackles are common with aftermarket springs, and more common with longer shackles, since you decrease shackle angle (more verticle) with greater length. See my writeup on ih8mud on relocating rear shackles.

Level with the frame is a bit much...45 degrees is the target, with the shackle angled back over the spring pack.

So basically what I am hearing is that he's got the wrong springs on the front. How long are 55 springs. Maybe I should search huh?

edit.
Ok did a search. Sounds like a 55 spring is 3" Longer than a 40 spring. I belive that the center pin hole is in the center of the spring also, correct?

3.5", 47" total, and yes it's a centered pin (23.5" eye to pin on both ends)